This invention relates to the removal of hardened cementitious material, known as grout, disposed between adjacent coplanar tiles in a wall or floor surface, and more particularly concerns a grout-removing power driven tool.
In the restoration or removal of tiled surfaces, it is often necessary to remove the grout from between the tiles. In the case of rectangular tiles laid in a square pattern, the grout is disposed in straight line patterns between the tiles. Because the width of the lines of grout may range between about 1/16" and 1/4", considerable precision is required in the removal method. Furthermore, good control is required of any tool employed in such application because slight misdirections can damage the tiles or cause breakage of the tool or tiles with consequent risk of injury to the operator.
A tool heretofore employed to remove grout disposed in straight lines between tiles is a manually operated device having a saw-like blade adapted to rest flat upon the line of grout. In use, the tool is manipulated in a back and forth motion while applying sufficient pressure upon the blade to reduce the grout to powder. A problem encountered with said prior manual device is that, at the end of each stroke, the powdered grout is compacted. Such compacting blocks or resists movement of the blade.
The use of a rapidly rotating device such as a rotary saw blade mounted in an electrically driven hand tool is undesirable because of the lack of control, and it high peripheral speed which presents potential danger from thrown fragments of tile or blade. Another generally available type of electrically powered hand tool is a jig saw or saber saw which drives a short saw blade in an up and down motion with respect to a motor-confining housing at variable rates up to 3,000 strokes per minute. Although the speed of the jig-saw blade can be controlled better than the speed of a rotary saw blade, the usual jig-saw motion is unsuited for use in grout removal because the depth of the grout layer is shallow generally less than 1/4", and the substrate underlying the grout may be unyielding. Although specialized power tools have been disclosed for grout removal, such tools are expensive and lack the versatility generally sought in power tools.
It is accordingly an object of the present invention to provide a device for removal of grout disposed in a straight path between tiles.
It is another object of this invention to provide a device as in the foregoing object which avoids a motion that would compact powdered grout within said path.
It is a further object of the present invention to provide a device of the aforesaid nature which avoids a high peripheral speed and affords control and safety during use.
It is still a further object of this invention to provide a device of the aforesaid nature which can be attached to a conventional electrically powered hand-held jig saw.
It is yet another object of the present invention to provide a device of the aforesaid nature of sturdy construction and amenable to low cost manufacture.
These objects and other objects and advantages of the invention will be apparent from the following description.